Btrfs: remove root_log_ctx from ctx list before btrfs_sync_log returns

commit cbd60aa7cd17d81a434234268c55192862147439 upstream.

We use a btrfs_log_ctx structure to pass information into the
tree log commit, and get error values out.  It gets added to a per
log-transaction list which we walk when things go bad.

Commit d1433debe added an optimization to skip waiting for the log
commit, but didn't take root_log_ctx out of the list.  This
patch makes sure we remove things before exiting.

Signed-off-by: Chris Mason <clm@fb.com>
Fixes: d1433debe7f4346cf9fc0dafc71c3137d2a97bc4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 0e044d7..1415f6d 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2850,6 +2850,7 @@
 
 	if (log_root_tree->log_transid_committed >= root_log_ctx.log_transid) {
 		blk_finish_plug(&plug);
+		list_del_init(&root_log_ctx.list);
 		mutex_unlock(&log_root_tree->log_mutex);
 		ret = root_log_ctx.log_ret;
 		goto out;